For the hyperstatic beam in Figure $3,$ the support D undergoes a counterclockwise rotation of $1/60$ radian, and support B undergoes a sag of $5$ mm$.$ Use the rotation method to:

$1.$ Determine the rotations at B and C;

$2.$ Determine the moments of continuity;

$3.$ Calculate the reactions at the supports and trace the DCL of each element;

$4.$ Draw diagrams of shear forces and bendin

Consider EI $=2500$ kNFigure $3$